The 19 year old has grown increasing close to Gordon, who was informally adopted by Houston when he was 12, following the death of her superstar mum in February, and the young couple first sparked rumours of a wedding in March, when Brown was snapped wearing a diamond sparkler on her ring finger.

The marriage speculation was denied and a representative for Brown was forced to dismiss fresh reports of a proposal in August after the couple tweeted a picture of the teen wearing what appeared to be a diamond and sapphire engagement ring.

However, it appears the wedding rumours are true after all - a new preview for The Houstons: On Our Own features footage of Brown and Gordon nervously announcing "We're engaged" to shocked family members.

The news was not well-received by relatives - Bobbi Kristina's aunt, Pat Houston, brands the news "unacceptable", while an uncle tells Gordon, "No one knew that from a godson, you would turn into a boyfriend, nobody knew that."

The trailer ends with a defiant Brown, the daughter of bad boy singer Bobby Brown, stating, "They wanna see us fail. I've got one thing to say: 'You won't!'"